HyperHEP B is a prescription hepatitis B immune globulin (human) used to prevent hepatitis B after exposure and to protect newborns at high risk. It delivers ready-made antibodies (anti-HBs) for immediate, short-term protection while the hepatitis B vaccine builds long-term immunity. Clinicians reach for it in time-sensitive moments: within hours of a needlestick, after sexual exposure to a person with hepatitis B, or in the delivery room for infants born to mothers who test positive. Because it is plasma-derived and given intramuscularly, HyperHEP B is handled with the same care as other blood products and follows precise timing and dosing rules. If you need a clear, practical guide to when to use it, how much to give, how to avoid common errors, and what risks to watch for, the sections below walk you through decisions step by step—so protection is fast, effective, and safe.
Essential Insights
- Provides immediate anti-HBs protection; best used as soon as possible after exposure.
- Typical adult or child dose after exposure: 0.06 mL/kg IM; infants at birth: 0.5 mL IM within 12 hours.
- Defer live vaccines such as MMR and varicella for about 3 months after HBIG.
- Avoid if history of severe reaction to human immune globulin; use caution with severe thrombocytopenia or bleeding disorders.
Table of Contents
- What is HyperHEP B and how it works
- Who should receive HyperHEP B and when
- How to dose and administer HyperHEP B
- Timing windows and special cases
- Side effects, precautions, and interactions
- What the evidence says about effectiveness
What is HyperHEP B and how it works
HyperHEP B is a hepatitis B immune globulin (HBIG) formulated for intramuscular injection. Unlike a vaccine, which trains the immune system to make its own antibodies over time, HyperHEP B supplies concentrated anti-HBs antibodies immediately. Those antibodies neutralize hepatitis B virus (HBV) and reduce the chance that an exposure leads to infection. The product is prepared from screened human plasma and undergoes multiple virus-reduction steps. Its potency is standardized against international reference material so each milliliter contains a defined minimum of anti-HBs activity. In practice, that consistency matters: it lets clinicians dose by body weight for exposures and use a fixed 0.5 mL dose for newborns.
A few pharmacologic features shape how HyperHEP B is used. After intramuscular injection, circulating anti-HBs appears within hours and typically persists for about 2 months, with an IgG half-life around 2 to 4 weeks. That limited duration is a virtue for post-exposure prophylaxis—strong coverage early, when it counts—but it also means you should pair HBIG with hepatitis B vaccination to build durable protection. Where long-term prevention is needed (for example, after a high-risk exposure in someone who is unvaccinated), the combination of HBIG plus vaccine is the standard approach.
Because it is an antibody product, HyperHEP B can blunt the response to certain live attenuated vaccines. The practical takeaway is simple: give HBIG when it is clearly indicated and then postpone live vaccines like measles-mumps-rubella (MMR) and varicella for approximately 3 months. Hepatitis B vaccine, however, is inactivated and may be administered at the same visit in a different limb without reducing its effectiveness. That is why newborns at risk routinely receive both HBIG and a hepatitis B vaccine dose within the first 12 hours of life.
Finally, HyperHEP B is strictly intramuscular. The preferred sites are the deltoid in older children and adults and the anterolateral thigh in infants and toddlers. The gluteal region is avoided because of variable absorption and the risk of sciatic nerve injury. If you treat patients with bleeding disorders or severe thrombocytopenia, balance the benefits of IM administration against bleeding risk and use careful technique with adequate pressure after injection.
In short: HyperHEP B offers immediate, standardized anti-HBs protection for a short window, is given intramuscularly, pairs seamlessly with hepatitis B vaccine, and requires a brief pause before live virus vaccines—features that define every dosing decision that follows.
Who should receive HyperHEP B and when
Use cases for HyperHEP B cluster into four groups: perinatal prevention, occupational exposures, sexual exposures, and certain household exposures in infants.
Perinatal prevention (newborns): Any infant born to a mother who tests positive for hepatitis B surface antigen (HBsAg) should receive HBIG 0.5 mL intramuscularly as soon as the infant is stabilized—ideally within 12 hours of birth—plus the first dose of hepatitis B vaccine in a separate limb at the same visit. The earlier HBIG is given, the better; effectiveness drops when administration is delayed beyond 24–48 hours. For medically stable infants weighing at least 2,000 grams, the vaccine series continues on the routine schedule. Preterm infants under 2,000 grams receive additional doses because the birth dose may be less immunogenic. All infants in this high-risk group should have post-vaccination serologic testing (HBsAg and anti-HBs) at age 9–12 months or 1–2 months after completing the vaccine series if the schedule is delayed.
Occupational and blood exposures: Unvaccinated or incompletely vaccinated individuals with percutaneous, mucosal, or ocular exposure to HBsAg-positive blood should receive HyperHEP B promptly (dose by weight; see the next section) and begin or complete the hepatitis B vaccine series. For vaccinated workers whose anti-HBs is unknown or below the protective threshold (<10 mIU/mL), post-exposure steps depend on the source patient’s HBsAg status and the exposed person’s antibody level. In non-responders—those who failed to achieve protective antibodies after two complete vaccine series—two doses of HBIG one month apart may be recommended if the source is HBsAg-positive or unknown.
Sexual exposures: Give HyperHEP B to unvaccinated persons after sexual contact with someone who is HBsAg-positive. The window of likely benefit extends up to about 14 days after the last sexual exposure, but earlier is better. Start the vaccine series at the same time. For vaccinated persons who never had post-vaccination testing, options include a booster dose of vaccine with or without HBIG depending on risk and timing.
Household exposures in infants: Infants younger than 12 months with a primary caregiver who has acute HBV infection should receive HyperHEP B and start the vaccine series. Older household contacts generally follow vaccination guidance rather than HBIG unless there is a discrete high-risk exposure.
In all scenarios, two timing rules steer decision-making: act as soon as possible, and respect the maximum effective window. For percutaneous exposures, protection is most reliable when HBIG is given within 24 hours (its value after 7 days is uncertain). For sexual exposures, aim to treat within 14 days. For newborns, 12 hours is the target. When in doubt about vaccine status or response, pair HBIG with initiation or completion of the vaccine series and arrange follow-up testing where indicated.
How to dose and administer HyperHEP B
Core dose rules
- Newborns at delivery: 0.5 mL IM within 12 hours of birth, in a limb different from the hepatitis B vaccine injection.
- Post-exposure (all ages beyond the neonatal dose): 0.06 mL/kg IM as soon as possible (preferably within 24 hours for needlestick and within 14 days for sexual exposure). Round volumes to practical syringe measurements and divide large volumes between sites if needed.
Where to inject
- Infants and toddlers: anterolateral thigh (vastus lateralis).
- Children, adolescents, adults: deltoid muscle.
- Avoid the gluteal region due to poor absorption and sciatic nerve risk.
How to pair with vaccine
- Give hepatitis B vaccine at the same visit in a different limb. HBIG does not blunt response to the hepatitis B vaccine.
- Do not mix HBIG and vaccine in the same syringe or site.
- For those starting the vaccine series after exposure, follow the product’s schedule (e.g., 0, 1, and 6 months or an adult two-dose schedule where applicable). Arrange post-vaccination serologic testing for groups where it guides care (e.g., infants born to HBsAg-positive mothers, health care personnel after exposure).
Repeat dosing
- Vaccine refusers or non-responders: a second HBIG dose 1 month after the first may be used in specific exposure scenarios.
- Ongoing exposure: if repeated or continuous exposure is likely, initiate or complete vaccination and consult exposure-management tables; some settings call for two HBIG doses one month apart.
Practical administration tips
- Calculate volume carefully. At 0.06 mL/kg, a 70-kg adult receives 4.2 mL—split into two deltoid injections (e.g., 2.1 mL per deltoid) to improve comfort and absorption.
- Use appropriate needles. For adults, a 22–25-gauge, 1–1.5-inch needle depending on body habitus; for infants, a 22–25-gauge, 1-inch needle.
- Apply firm pressure for 2 minutes after injection in patients with bleeding risk.
- Check product and storage. Use single-dose vials or prefilled syringes. Store at 2–8°C; never freeze; discard any unused portion.
- Document lot and site. Record the product, dose (mL), lot number, expiration date, and injection site; for perinatal use, also document maternal HBsAg status and infant timing.
Do not administer intravenously. HBIG formulations for IV use exist for other indications, but HyperHEP B is intramuscular only. If IV access is required for other reasons, it does not change the HBIG route.
By applying these rules—dose by weight or use the fixed neonatal dose, inject IM in the right muscle, pair with vaccine, and consider a second HBIG dose in non-responders—most clinical situations can be handled quickly and correctly at the point of care.
Timing windows and special cases
Clock management after exposure
- Needlestick, bites, splashes to eye or mucosa: administer HyperHEP B as soon as possible, ideally within 24 hours. The benefit after 7 days is uncertain; do not delay while awaiting complete lab results if the source is likely HBsAg-positive.
- Sexual exposure: administer within 14 days of the last exposure. Start or complete vaccination concurrently.
- Newborns of HBsAg-positive mothers: administer within 12 hours of birth; effectiveness declines with delay and may drop sharply after 48 hours.
When vaccine history is uncertain
If a person reports vaccination but lacks records and post-vaccination antibody testing, manage the exposure conservatively: test anti-HBs when feasible and treat based on risk. Many algorithms call for one dose of HBIG plus a vaccine booster for low or unknown anti-HBs after a significant exposure to an HBsAg-positive or unknown source. If anti-HBs is ≥10 mIU/mL, HBIG is generally not required.
Vaccine non-responders
A true non-responder is someone with anti-HBs <10 mIU/mL after two complete hepatitis B vaccine series. After significant exposure to an HBsAg-positive or unknown source, give two HBIG doses 1 month apart. Because long-term vaccine-induced immunity is unlikely in this group, they should be counseled on exposure avoidance and the need for HBIG after future exposures.
Preterm and low-birth-weight infants
Infants <2,000 grams born to HBsAg-positive mothers receive HBIG 0.5 mL IM within 12 hours plus a birth-dose hepatitis B vaccine; the birth dose may not count toward the primary series, so these infants follow a four-dose schedule beginning at 1 month of age. If the maternal HBsAg status is unknown at delivery, give vaccine within 12 hours to all infants; for those under 2,000 grams, give HBIG within 12 hours as well. If the mother is later found to be HBsAg-positive, give HBIG to infants ≥2,000 grams no later than 7 days of age.
Live vaccines after HBIG
Because passively transferred IgG can interfere with the response to live vaccines, defer MMR and varicella for about 3 months after HBIG. This deferral does not apply to inactivated vaccines, including the hepatitis B vaccine given at the same visit as HBIG.
Repeat or ongoing exposures
For sexual partners of people with chronic HBV infection, the priority is complete vaccination and confirming protective antibodies. HBIG is used for discrete high-risk exposures or when immediate protection is essential and vaccination status is incomplete or non-protective. In occupational settings with repeated exposures, establish baseline anti-HBs, give boosters or revaccinate as needed, and keep clear protocols for rapid HBIG access.
If HBIG is delayed beyond the window
When the indicated time window has passed, HBIG’s benefit is limited or uncertain. In that case, vaccinate without delay and arrange follow-up testing per risk level. For infants, if the recommended perinatal prophylaxis was missed, consult pediatric infectious diseases or public health guidance promptly; catch-up plans depend on infant age, maternal status, and prior doses received.
These “special case” rules are essentially timing and documentation rules. If you keep the windows straight (12 hours for newborns, 24 hours for needlestick, 14 days for sexual exposure) and confirm vaccine response when it changes management, you will protect most patients who need help fast.
Side effects, precautions, and interactions
Common reactions are generally mild and short-lived: pain and tenderness at the injection site, and occasionally headache, malaise, nausea, or low-grade fever. Local reactions are more likely with larger volumes, which is one reason to split adult doses across two sites.
Serious reactions are rare but possible. As with other human immune globulin products, anaphylaxis can occur. This risk is higher in people with a history of severe reactions to human immune globulin. Epinephrine and resuscitation equipment should be immediately available wherever HBIG is administered. True IgA deficiency with anti-IgA antibodies is an additional theoretical risk factor for hypersensitivity to immune globulin products; take a careful history and proceed in settings prepared to manage anaphylaxis.
Bleeding risk and IM injections: Patients with severe thrombocytopenia or coagulation disorders may bleed after IM injections. In such cases, give HBIG only if the anticipated benefit outweighs the risk. Use the smallest practical gauge needle, apply firm pressure for at least 2 minutes, and consider timing with factor replacement when appropriate.
Vaccine interactions: Defer live attenuated vaccines (MMR, varicella) for about 3 months after HBIG, because passively acquired antibodies can reduce their effectiveness. Inactivated vaccines—including the hepatitis B vaccine—may be given at the same visit in a different limb. This pairing (HBIG + vaccine) is standard after exposures and at birth for at-risk infants.
Drug interactions: No clinically significant drug–drug interactions are known for HBIG. The product is not expected to alter laboratory tests aside from transiently influencing hepatitis B serologies due to passive anti-HBs; time post-vaccination testing accordingly (e.g., test infants at 9–12 months or 1–2 months after the final vaccine dose while allowing sufficient time after HBIG so passively transferred antibodies have waned).
Pregnancy and lactation: For pregnant patients needing post-exposure prophylaxis, HBIG may be used when clearly indicated; decades of clinical experience support its use in this setting. For lactating individuals, no special precautions are generally required beyond standard monitoring.
Product composition and handling: HyperHEP B contains 15–18% protein stabilized with glycine and no preservative. It is supplied as single-dose vials or prefilled syringes and is not made with natural rubber latex. Store at 2–8°C; do not freeze. Inspect visually for particulate matter and discoloration before administration.
When to avoid or delay: Do not give HyperHEP B intravenously. Avoid the gluteal muscle as an injection site. If a patient had a prior severe reaction to immune globulin, consult allergy/immunology or infectious diseases for risk–benefit assessment and premedication strategies. If a live vaccine is urgently needed (rare), discuss timing with specialist guidance.
Bottom line: most patients tolerate HyperHEP B well, but be prepared for rare allergic reactions, protect patients at bleeding risk with careful technique, and keep live-vaccine timing rules front and center.
What the evidence says about effectiveness
Perinatal prevention: The combination of HBIG at birth plus a complete hepatitis B vaccine series prevents the chronic carrier state in roughly 85–95% of infants born to HBsAg-positive mothers, with protection strongest when both products are given within 12 hours and in separate limbs. Vaccine alone and multiple HBIG doses alone are less effective than the combination, especially when maternal viremia is high. For mothers with very high HBV DNA levels during pregnancy, maternal antiviral therapy in the third trimester plus standard newborn prophylaxis further reduces risk.
Post-exposure prophylaxis (occupational): For unvaccinated people with percutaneous or mucosal exposure to HBsAg-positive blood, HBIG plus initiation of vaccine is the recommended course. A single HBIG dose provides immediate coverage; initiating the vaccine series creates long-term protection. In vaccine non-responders, two HBIG doses one month apart are used after significant exposure. Effectiveness is highest when HBIG is given promptly—ideally within 24 hours of exposure—and declines with delay beyond 7 days for needlestick injuries.
Sexual exposure: A single HBIG dose administered within 14 days of last sexual contact with an HBsAg-positive partner reduces transmission risk; starting the vaccine series at the same time ensures future protection. For vaccinated individuals without prior antibody testing, a booster with or without HBIG may be used based on risk and timing.
Duration and kinetics: After an intramuscular dose, passive anti-HBs levels typically persist for about 2 months—consistent with the IgG half-life of ~18–25 days. That pharmacology underlies the advice to combine HBIG with vaccine rather than relying on repeat HBIG alone, except in narrow circumstances such as vaccine refusal or documented non-response.
Why timing matters: HBV is highly infectious and can remain viable on surfaces for at least 7 days. Neutralizing antibody levels are most protective early, when inoculum is small and replication is just beginning. The longer the delay, the more likely the virus has seeded infection beyond what passive antibodies can block—hence the 12-hour, 24-hour, and 14-day rules for newborns, needlesticks, and sexual exposure, respectively.
Quality of evidence: The recommendations supporting these practices come from large public-health programs, observational cohorts, controlled trials in perinatal settings, and decades of real-world experience encoded in national guidelines and product labeling. Together, they show a coherent picture: HBIG provides a time-limited shield, and when paired with vaccination, it dramatically reduces the risk of infection in the highest-risk moments.
In practical terms, if you treat early, dose correctly, and pair with vaccine, HyperHEP B delivers reliable protection exactly when patients need it most.
References
- DailyMed – HYPERHEP B (hepatitis b immune globulin- human injection 2024 (Label)
- Chapter 10: Hepatitis B | Pink Book | CDC 2024 (Guidance)
- Hepatitis B Perinatal Vaccine Information | Hepatitis B | CDC 2025 (Guidance)
- Prevention of Hepatitis B Virus Infection in the United States: Recommendations of the Advisory Committee on Immunization Practices | MMWR 2018 (Guideline)
Disclaimer
This article is informational and is not a substitute for professional medical advice, diagnosis, or treatment. Medication and immunization decisions should be made by qualified clinicians using current guidelines, product labeling, and the patient’s medical history. If you think you have been exposed to hepatitis B, seek medical care immediately.
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